Packaging material



N. S. PAVA PACKAGING MATERIAL Nov. 16, 1965 2 Sheets-Sheet 2 Filed Sept. 25, 1963 INVENTOR. AVA

BY $771M damn? S 3,218,178 Patented Nov. 16, 1965 3,218,178 PACKAGING MATERIAL Norman S. Pava, 126 Woodside Terrace, Springfield, Mass.

Filed Sept. 23, 1963, Ser. No. 310,742 2 Claims. (Cl. 99171 This invention relates to packaging sheet materials and more particularly to a type of material which serves to protect the packaged products from damage during shipment and display.

The principal object of this invention is to provide an inexpensive packaging sheet material which is characterized by a high degree of shock absorption and crush resistance, while at the same time providing for attractive and compact packaging.

Another object of this invention is to provide a protective, transparent packaging material characterized by its versatility for packaging a wide variety of articles, including irregularly shaped articles whereby the material is useful in fulfilling the long standing need of a suitable packaging material for fresh produce, such as bananas and the like.

A further object of the invention is to provide a sheet packaging material which will minimize spoilage of produce caused by moisture within the package.

The objects of this invention are attained in general by providing a resiliently stiff sheet material having a plurality of closely spaced projections extending outwardly from one of its surfaces and a grid on its opposite surface.

The above and other related objects and features of the invention will be apparent from a reading of the following description of the disclosure found in the accompanying drawing and the novelty thereof pointed out in the appended claims.

In the drawing:

FIG. 1 is a plan view of a sheet of packaging material embodying the present invention;

FIG. 2 is a section, on an enlarged scale, taken along line II-II in FIG. 1;

FIG. 3 is a section, on an enlarged scale, taken along line III--III in FIG. 1;

FIG. 4 is a section, on an enlarged scale, taken along line IV-IV in FIG. 1;

FIG. 5 is a section taken on line VV in FIG. 2;

FIG. 6 is a view showing a bunch of bananas wrapped in the present packaging material; and

FIG. 7 is a side view showing another form of banana package embodying this invention.

Wrapping material embodying this invention may be formed of any suitable material, preferably transparent, having properties which enable it to be wrapped around variously shaped articles and to afford a high degree of product protection commensurate with low cost, attractive and compact packaging.

Suitable materials for carrying out this invention include biaxially oriented polystyrene, certain vinyl sheet materials, and cellulose acetate. Biaxially oriented polystyrene has been found particularly well suited for making packaging material embodying my invention because of its commercial availability at relatively low cost. Moreover, polystyrene is preferable because of its relative rigidity or stiffness which provides crush-resistance in relatively thin sheets. Sheet material on the order of .003.007 inch is suitable for the majority of packaging uses. In addition, polystyrene can be pressure or vacuum formed so that it can be economically formed into the unique configuration hereinafter described. Furthermore, polystyrene is preferable because of its high gloss and clarity which enhances the attractiveness of packages in which it is used.

The packaging material of the present invention, as seen in FIGS. 1-5, is characterized by a plurality of projections or protuberances 10 which as shown are disposed in rows lengthwise and across the sheet. Between the protuberances the sheet is not flat, but is continuously and reversely curved forming on the opposite side a waflle-like gn'd having ridges 12 with curved crests.

While not necessarily so limited in use, it has been found preferable that the grid surface of the sheet material be placed against the product being packaged with the protuberances 10 projecting from the outer surface of the package formed thereby, as illustrated in FIG. 6.

The configuration of the protuberances 10 is generally that of a truncated four-sided pyramid, and as viewed in a plane parallel to the sheet, the sides 14 of the pyramids (FIG. 5) are gently convexly curved and joined by curved corners 15. The sides 14 are also of concave curvature when in a plane perpendicular to the sheet (FIG. 2). The outer ends or truncated portions of the protuberances 11) are defined by dome-shaped portions 16 having a gentle convex curve and joined to the sides of the pyramids by curved corners 17 (FIG. 2). Of course, the depressions on the opposite side of the sheet, corresponding to the protuberances, having the opposite configuration.

The n'dges 12 as considered from the upper surface of the packaging material are convexly curved throughout their lengths in any section transverse to their lengths. Thus, a transverse section taken centrally through the protuberances 10 (FIG. 2) shows the ridges 12 to be joined to the concave sides thereof (the convex sides of the corresponding depressions) by smoothly blended curves. The ridges 12 are also convexly curved at their intersections and concavely curved therebetween at points 18 aligned with the protuberances 10 by reason of their undulant shape in a longitudinal direction (see FIG. 3).

The undulant form of the ridges 12 also results in smaller protuberances 20 on the inner surface of the packaging material. These smaller protuberances blend with the depressions opposite the protuberances 10 along smoothly curved lines, as can be seen from FIG. 4.

FIG. 6 shows the present packaging wrapped about a hand of bananas. The ends of the sheet may be joined by various means such as heat sealing, pressure sensitive tape, stapling, etc. For packaging the sheet may have uncontoured marginal edges, as shown at 23 in FIG. 7, facilitating the joining together of the edges when forming a package. Another way of forming the package is to enclose bananas in side-by-side relation so that the package is flat, as shown in FIG. 7, and may be readily stacked with other similarly packaged bananas.

The present packaging material has several advantages, the most notable of which are its superior shock and crushresistance which, in the case of produce such as bananas, prevent or minimize any pressures which would bruise or otherwise damage the produce. In addition, this material can be provided at low cost so as to make its widespread use commercially practical.

As for the shock absorbing and crush resisting characteristics, it will be noted that contact of the produce with external objects and surfaces is primarily via the smoothly curved low protuberances 14. Any contact with the outer surface of the package will generally be against the domes 16 of the protuberances 10. Increasing pressure on the gently curved surfaces of these domes will cause them to give or flex inwardly with minimum force being transmitted to the walls of the pyramidal protuberances 4. If a greater pressure or shock is sustained, the walls 14 of protuberances 10 will be flexed inwardly prior to transmittal of the force directly to the ridges 12 and protuberances 20 on the inner surface of the package in contact with the product.

The sheet configuration is such that shock and crushing of the product will first be resisted by fiexure of the domes 16, then by fiexure of the sides of pyramidal protuberances ill, and finally by fiexure of the ridges 12 and protuberances 29, as pressure is transmitted to the product packaged therein. While all portions of the material may yield simultaneously, the order of fiexure set forth indicates the portions of the sheet which will tend to yield first to the greatest extent.

The resilience and strength of the biaxially oriented polystyrene resists permanent deformation of the sheet itelf so that it will tend, in most instances, to return to its original configuration once any normal pressure thereon is removed, and can continue to function as described, when subjected to repeated pressures.

The low cost of my packaging material may be first attributed to the basic low cost of the biaxially oriented polystyrene and its ability to be economically formed into the desired configuration by vacuum forming. Also of importance is the ease with which it may be handled in Wrapping both regularly and irregularly shaped objects. The curvature of the surface also allows the polystyrene (which is essentially unstretchable) sheet to be stretched to some extent where necessary. Furthermore, it may be economically formed into a Wrapper, as pointed out above, by stapling, hear sealing or pressure sensitive tape, as best fits the needs of a given use.

Also, the relatively high rigidity of the biaxiany oriented polystyrene and its resistance to fiexure, enables the above-described shock absorbing and crush resisting functions to be obtained with a relatively thin material to further minimize the cost involved. An important value of the invention is that useful additional stillness is imparted to this thin material as a result of the contours of the protrusions and ridges. The material is crease resistant since there are virtually no lines along which a fold can be made without distorting a contour. Thus, while the material may indeed be folded where necessary, it nevertheless is considerably stiffer and more crease resistant than the uncontoured base material. This additional stiffness makes it possible to make a selfsupporting package of the material simply by folding it upon itself or by wrapping it around articles. Where the articles are loose or flexible, the stiffness of the package not only supports the package itself but also supports the contained articles.

Many products, such as produce, are most vulnerable to damaging during shipment. The present packaging material not only gives protection at this time, but also serves as an attractive display package for retail merchandising, particularly because of its high clarity and, of course, protection of the produce from bruising when on display.

A further advantage of this packaging material is particularly evident in packaging fresh produce. Thus, there is a tendency for moisture to condense Within the package 4. whether or not it is vented. Preferably, perforations 21 are provided to provide for air circulation and discharge of moisture. The protuberances 2% not only serve to space the product from the main area of the packaging material so that there is a substantial ventilation of the product with little or no opportunity for moisture to become intimately trapped between it and the packaging material and thereby promote fungus or decay.

As shown in FIG. 7 the packages may be stacked with the protuberances of one package nesting into the troughs of the adjacent packages. This provides an interlock of adjacent packages whereby the packages are securely stacked, with minimum danger of toppling and shifting relative to each other. It also permits a maximum number of packages to be fitted into a minimum of space. Another advantage of the packaging material embodying this invention is that the sheets can be nested prior to use.

There is an additional aspect of the nesting of the protuberances into the troughs: since the nesting is not perfect, the faces of adjacent packages are not in intimate contact with each other over their whole area; there are regular, connected interstices between adjacent packages which provide channels for air circulation. This is a very important feature.

Having thus described the invention, what is claimed as novel and desired to be secured by Letters Patent of the United States is:

package comprising bananas disposed Within a synthetic plastic material comprising at least one sheet of synthetic plastic material having a pattern of closely spaced protuberances projecting outwardly of the package and a grid of intersecting ridges on the inner surface of said package, said ridges being undulant and convexly curved and cushioning said bananas within the package, said protuberances being provided with holes through the outer ends thereof providing ventilation to the bananas within said package.

2. A banana package as set forth in claim 1 in which said synthetic plastic material is transparent, biaxially oriented polystyrene, and in which said protuberances have concavely curved side walls providing air spaces between stacked, identical banana packages, both said air spaces and the holes in said protuberances providing ventilation to the bananas within said package.

References Cited by the Examiner UNITED STATES PATENTS 2,439,7l6 4/1948 Caniield et al.

2,549,069 4/195l Donofrio 20656 2,893,550 7/1959 Sandmeyer 206-65 2,917,223 12/1959 Le Bolt et al.

3,018,015 1/1962 Agriss et al. 21753 3,097,787 7/1963 Schur.

2 131,846 5/1964 Whiteford 229-2.5

THERON CONDON, Primary Examiner. 

1. A PACKAGE COMPRISING BANANAS DISPOSED WITHIN A SYNTHETIC PLASTIC MATERIAL COMPRISING AT LEAST ONE SHEET OF SYNTHETIC PLASTIC MATERIAL HAVING A PATTERN OF CLOSELY SPACED PROTUBERANCES PROJECTING OUTWARDLY OF THE PACKAGE AND A GRID OF INTERSECTING RIDGES ON THE INNER SURFACE OF SAID PACKAGE, SAID RIDGES BEING UNDULANT AND CONVEXLY CURVED AND CUSHIONING SAID BANANAS WITHIN THE PACKAGE, SAID PROTUBERANCES BEING PROVIDED WITH HOLES THROUGH THE OUTER ENDS THEREOF PROVIDING VENTILATION TO THE BANANAS WITHIN SAID PACKAGE. 